Heat and Expansion

Description
"A list of thermometric properties is given along with an explanation of thermal equilibrium . Fixing the upper and lower fixed points of a temperature scale, using it to determine any unknown temperature are also discussed. Coefficients of linear expansion and its calculation for an actual rail road is interesting. Two pictures show a bridge and a railway track where these facts were used.Also the expansion of a brass bar is shown using a device which amplifies the expansion The working of a bimetal is explained as a consequence of linear expansion. Taking some exact values the expansion is calculated. Uses of Bimetals and an experiment to show how the bimetal bends is also included. An interesting use of a bimetal is in a coffee maker where a bimetallic strip behaves like a valve. Bimetals can be used as a thermometer. Here an actual one with a coil is shown to work.Coefficient of volume expansion is derived from linear dimensions. The values of the coefficient for Mercury and Pyrex is mentioned which leads to the fact why Mercury is chosen as thermometric liquid. The brass ball and ring experiment shows the expansion of metal in a unique way The phenomenon of anomalous expansion is explained. Related effects described are water at the bottom of freezing pond and floating of ice in water."

Prof. Walter Lewin, 8.01 Physics I: Classical Mechanics, Massachusetts Institute of Technology: MIT OpenCourseWare), http://ocw.mit.edu (Accessed June 15, 2011). License: Creative Commons BY-NC-SA: http://ocw.mit.edu/terms/#cc